Microbiological impressions of teeth, saliva and dietary fibre can predict caries activity.

OBJECTIVES: Mutans streptococci and Lactobacilli on impressions of teeth and caries tests were used to identify caries prone subjects. METHODS: Twenty-seven dental students were examined for caries initially and after 4 years. At the initial examination plaque index; saliva flow, buffering capacity and lysozyme; sucrose and fibre consumption; Lactobacilli and mutans streptococci in saliva and on alginate impressions were measured. Data was analysed using Kruskal-Wallis, Wilcoxon-Mann-Whitney and Spearman's Rank correlation tests and linear discriminant analysis. RESULTS: The best predictor of caries increment was decay. Nine subjects had no caries or restored teeth with caries (Group A); 9 had restored teeth with no caries but developed an average of 8 new decayed surfaces (Group B); 9 had an average of 4.4 decayed surfaces and developed a further 9.6 (Group C). Group A had fewer filled surfaces than Group B (p=0.02) and Group C (p=0.024) a higher flow rate of stimulated saliva than Group B (p=0.02) and Group C (p=0.012). Microorganisms were cultured from all decayed teeth, 98% that developed decay, 89% filled and 69% sound teeth. Fibre intake, saliva flow and the percentage of teeth or sound teeth with Lactobacilli and mutans streptococci gave a specificity of 89%, a sensitivity of 100% and predicted an increase in decay in all Group B subjects while one subject from Group A was misclassified. When teeth with microorganisms were excluded four subjects were misclassified. CONCLUSIONS: Growth of cariogenic microorganisms on alginate impressions, saliva flow and dietary fibre predicted caries activity in most subjects.

Frequency of food items consumed by young rural and urban African children--essential knowledge to provide dietary advice in caries prevention.

AIMS: To determine the variety and frequency of consumption of food items, including cariogenic items, among 4-24-month-old black South African children. SETTING AND PARTICIPANTS: A rural area of low socioeconomic status, Ndunakazi, KwaZulu/Natal Province [n=105]; two urban areas in Gauteng Province: Soweto (low to middle socioeconomic status) [n=100], and the northern suburbs of Johannesburg and Sandton (middle to upper socioeconomic status) [n=101]. METHODS: Dietary intake was assessed using a food frequency questionnaire and analysed using SAS. OUTCOME MEASURES: Weekly frequencies for: number of times each food item was recorded; total consumption for each food item for the combined group of children and the three individual geographical areas. Food items were ranked in descending order according to the combined group of children within five selected food groups (carbohydrates, sugars, fruit and vegetables, milk and milk products, other foods and snacks). Only individual area results were listed. RESULTS: The preferred foods and frequency of consumption of these foods were identified. Significant differences were found between rural and urban groups for most of the food items, but not between urban groups. Food items were 'flagged' according to their cariogenic potential. CONCLUSION: The study provided valuable new information suitable for adapting and developing dietary advice relevant to caries prevention in African children

Energy and macronutrient intake in relation to dental caries incidence in urban black South African preschool children in 1991 and 1995: the Birth-to-Ten study.

OBJECTIVE: To study energy and macronutrient intake in relation to dental caries incidence among urban black South African children at the ages of 1 and 5 years. DESIGN AND SUBJECTS: Food frequency questionnaires and WHO caries diagnostic criteria were used. The study sample of 1639 urban black children with nutrition and dental information from the 1991 and/or 1995 Birth-to-Ten (BTT) Study interceptions comprised true longitudinal (n = 259) and cross-sectional (n = 1216 for 1991 and n = 164 for 1995) subjects. For the longitudinal group true dmfs (decayed, missing, filled surfaces) incidence and average intakes of energy and macronutrients between 1991 and 1995 were calculated. SETTING: South Africa. RESULTS: Median macronutrient intakes were not significantly different between the cross-sectional and longitudinal samples. Dental caries prevalences at age 1 were 1.2% and 1.5% for the cross-sectional and longitudinal samples, respectively. By age 5 these values were 60.4% and 62.2%, respectively. The median dmfs score at age 1 was 0. At 5 years this was 2 for all children and 5 for those with caries. Statistical analysis for trend at age 5 showed a significant increase in caries prevalence with increasing energy, carbohydrate and added sugar in the cross-sectional sample only. The only significant changes in dmfs scores were seen for energy and added sugar for the whole sample. The r values between log(dmfs incidence + 0.3) and the average nutrient log variables were low, and a general linear models analysis showed no statistically significant effects on log(dmfs incidence + 0.3) of any of the log nutrient variables. CONCLUSIONS: For the relationship between macronutrient intake and caries (prevalence and incidence), a cross-sectional and true longitudinal study gave similar results.

Energy, macro- and micronutrient intake of 5-year-old urban black South African children in 1984 and 1995.

Food habits change over time. This paper reports results of nutritional studies among 5-year-old urban black children in 1984 and 1995 in the Johannesburg/Soweto area. The objective was to compare energy, macro- and micronutrient intake of 5-year-old urban black South African children. Dietary intake was assessed by detailed dietary histories in 1984 and food frequency questionnaires in 1995, conducted by trained interviewers. The intake of energy, macro- and most micronutrients was higher in 1995 than in 1984, except for vitamin A, ascorbic acid, copper and iron. Fat intake increased from 52 g/day in 1984 to 95 g/day in 1995. Only biotin and vitamin D fell below 67% of the recommended dietary allowances (RDA) for 4- to 6-year-olds, but mean intakes concealed the high percentage of children that had intakes below the RDA in 1984 and 1995. Urban black 5-year-old South African children consumed a low-fat (30% of total energy), high-carbohydrate (61% of total energy) diet in 1984, but a typical westernised diet by 1995 (fat 41% and carbohydrate 52% of total energy). With these changes, current reliable nutrition information is needed to assess the existing and future health needs of all South Africans.

Energy and macronutrient intake of one-year-old South African urban children: the Birth to Ten (BTT) Study.

With the changing situation in South Africa, new, reliable, longitudinal nutritional information on young children is needed. Part of the objective of the Birth to Ten (BTT) Study (1990-2000) in the Soweto-Johannesburg area, is to assess the nutrient intake of children. For each of the 2059 one-year-old children mean nutrient intake was determined using food frequency intakes, determined through interviewing parents or guardians. Urban 'coloured' children had the highest daily intake of all the macronutrients, energy being significantly higher than the other groups. Urban black children had the lowest macronutrient intake and energy was significantly lower than that of white children. All groups consumed a typical westernised diet, low in unrefined carbohydrate (47-49% of energy), but high in protein (200% of Recommended Dietary Allowances (RDA)) and fat (38-40% of energy). Among the 'black', 'coloured' and 'white' clinics a difference of approximately 300 kcal/day was noted between the highest and the lowest energy intakes, Pimville and Mofolo showing significantly higher differences among the 'black' clinics. Among the 'coloured' clinics Westbury had a significantly higher energy intake than Eldorado Park. Results have indicated that one-year-old 'coloured' and white children had adequate nutrient intakes, but black and Indian had inadequate energy intakes based on RDA and excluding the contribution of breast milk.

Energy intake, dental caries and periodontal disease in 11-year-old black children in two regions of Southern Africa: KwaZulu and Namibia.

The study examined energy intake in relation to dental caries and periodontal disease in 11-yr-old rural and urban black children in low fluoride areas of KwaZulu and Namibia (0.15 ppm F) and one higher fluoride area of Namibia (1.56 ppm F). Twenty-four hour dietary recalls were conducted by trained interviewers and daily energy intake estimated using the MRC dietary analysis programme. DMFS was recorded according to WHO criteria: periodontal disease was measured using CPITN and SAS was used for statistical analysis. The prevalence of dental caries and periodontal disease (using CPITN), were compared within three energy groupings; < or = 850 kcal/day; > 850, < 1400 kcal/day and > or = 1400 kcal/day. The rural low fluoride Namibian children had the lowest mean energy intake (616 kcal/day), which also was the grouping with highest healthy periodontal prevalence (65%). The urban groups had higher energy intakes than the rural communities. Statistically significant effects on caries prevalence were seen for country and fluoride grouping; for periodontal disease, significant effects were noted for country, fluoride group and environment. Energy intake had no statistically significant effect, so this is not a risk marker for the disease.